Started the 12v conversion this weekend by picking up a GM 1 wire alternator from the local NAPA store. The first thing I noticed was the late model GM pulley has a slightly wider V groove than the generator pulley. With them both having the same shaft diameter, the first change was to install the 1952 Fomoco pulley on the alternator. Next, to keep the belts aligned, the rear mounting locations of the pulley were compared to the rear of the mounting bracket location. Although the front face of the generator is recessed, this was the same as the thickness of the mounting bracket, so it was a wash in this case. (generator has mounting bracket on back side of tab, on alternator it mounts in front)  We came up with a difference of 7/16" between the position of the two, so the bracket will need some slight modification to keep the belt positioned.
 
 

 
 

 
 

 
 
Prior to cutting the bracket, measurements were taken between the hole c-c for future reference.
 
 

 
 

 
 

 
 
A 1/2-13 hex nut is about perfect for a 7/16" high spacer
 
 
 

 
 

 
 

 
 
The rear generator bracket is rotated around to pick up the rear of the alternator bolt. The rear bolt is in a water jacket, in case things look a little damp in the pictures. (I got a little damp too!)
 
 

 
 
Looks like a spacer of about 3/4" long will be needed.
 
 

 
 
The lower bolt is slightly off, and positions the alternator a bit too close to the engine for my liking.
 
 

 
 

 
 
In the interest of not dismantling the complete engine, an add-on bracket is used.
 
 

 
 

 
 

 
 

 
 
And that will be all for this weekend, as I'll need to get a slightly longer V belt now.

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